Influence of impurity on binding energy and optical properties of lens shaped quantum dots: Finite element method and Arnoldi algorithm

•Effect of impurity position on binding energy in a lens-shaped quantum dot is studied.•Finite element method and the Arnold algorithm is are used for various impurity locations.•Impurity location plays an important and considerable role in the electronic and optical properties.

In the present work, we have studied the effects of the impurity position on the donor binding energy and optical properties of a lens shaped quantum dot with a finite confining potential. To this end, we have calculated the energy levels, wave functions and the binding energy using the finite element method and the Arnold algorithm for various impurity locations. Applying the compact density matrix and an iterative method, the refractive index changes and absorption coefficients have been determined in the presence of the impurity. Our results show that the binding energy decreases when the quantum dot height and radius increase. The absorption coefficients and refractive index changes decrease and shift toward the higher energies in the presence of the impurity. Generally, the impurity location plays an important and considerable role in the electronic and optical properties of a lens shaped quantum dot.